Serotonin (5-hydroxytryptamine or 5-HT) is present in animals, plants, fruits, and nuts. Inside the body, serotonin is produced from an amino acid, tryptophan. Serotonin is formed in the body by hydroxylation and decarboxylation of the essential amino acid L-tryptophan. In the biosynthesis of serotonin from L-tryptophan, L-tryptophan is hydroxylated in the presence of the enzyme tryptophan hydroxylase to form the intermediate product L-5-hydroxytryptophan (L-5-HTP). This intermediate product is decarboxylated in the presence of the enzyme 5-hydroxytryptophan decarboxylase to form serotonin. By the term "serotonin precursor" is intended L-tryptophan, L-5-hydroxytryptophan, pharmacologically equivalent analogues of L-trytophan and L-5-hydroxytryptophan and pharmaceutically acceptable salts of L-tryptophan and L-5-hydroxytryptophan.
Serotonin or serotonin deficiency has been implicated in the treatment or the cause of various medical disorders including depression, premenstrual syndrome, migraine headaches and obesity. To date medications or "homeopathic" preparations attempt to raise serotonin levels inside the body act by inhibiting serotonin uptake systems or increasing the endogenous production of serotonin. It has recently been implicated that the oral administration of certain serotonin precursors or artificial serotonin production facilitators results in harmful side effects, such as eosinophilic-myalgia syndrome, heart valve disfunction and pulmonary hypertension.
It has previously been believed that oral administration of serotonin was not therapeutically effective since serotonin was readily oxidized in the gastrointestinal tract thereby derivatizing the serotonin into non-therapeutic compositions. Therefore "serotonin precursors", such as L-tryptophan, capable of being transformed into serotonin in the body have been orally administered for the treatment of various medical conditions.
It is therefor desirable to orally administer serotonin without using serotonin precursors in a manner effective to administer serotonin into the bloodstream.